Miyague Andre H, Pavan Theo Z, Soares Carlos A, De Catte Luc, Nastri Carolina O, Welsh Alec W, Martins Wellington P
Department of Obstetrics and Gynecology, Medical School of Ribeirão Preto (A.H.M., C.A.S., C.O.N., W.P.M.), and Department of Physics, School of Philosophy, Sciences, and Letters of Ribeirão Preto (T.Z.P.), University of São Paulo, Ribeirao Preto, Brazil; Department of Obstetrics and Gynecology, University Hospital Evangelico, Curitiba, Brazil (A.H.M.); Woman and Fetal Medicine Institute, Curitiba, Brazil (A.H.M.); Ultrasonography and Retraining Medical School of Ribeirão Preto, Ribeirão Preto, Brazil (C.A.S., C.O.N., W.P.M.); Department of Obstetrics and Gynecology, University Hospitals Leuven, Leuven, Belgium (L.D.C.); School of Women's and Children's Health, University of New South Wales, Randwick, New South Wales, Australia (A.W.W.); and Department of Maternal-Fetal Medicine, Royal Hospital for Women, Randwick, New South Wales, Australia (A.W.W.).
J Ultrasound Med. 2015 Dec;34(12):2245-51. doi: 10.7863/ultra.15.01021. Epub 2015 Nov 5.
To determine the influence of the pulse repetition frequency (PRF) and wall motion filter on the 3-dimensional (3D) power Doppler vascularization-flow index (VFI) and volumetric pulsatility index (PI) obtained from spatiotemporal image correlation (STIC) data sets acquired from a common carotid artery of a healthy participant.
We acquired 11 STIC data sets, 1 for each PRF value ranging from 0.6 to 9.0 kHz. Vascularization-flow index and volumetric PI values were determined from the 440 static 3D data sets contained in these STIC data sets. Additionally, 3 sets of radio-frequency data were acquired for offline processing of different wall motion filter values for PRF values of 0.6, 3.3, and 10 kHz.
We constructed VFI curves and observed 2 patterns: a flattened pattern with a low PRF and a triphasic pattern with a high PRF, correlating with the known pulsed wave Doppler profile of this vessel. Volumetric PI values were around 0 for low PRF settings and increased with increasing PRF. Analysis of the radiofrequency data showed that increasing wall motion filter values gradually filtered out the low-velocity power Doppler signals while retaining the higher-velocity ones, allowing the distinction of integrated power Doppler signal velocity throughout the cardiac cycle.
We conclude that the PRF and wall motion filter dramatically influence 3D power Doppler indices and the volumetric PI, and the use of PRF values in which minimum VFI values are measured during the diastolic phase in the spectral Doppler wave may validate the use of the volumetric PI.
确定脉冲重复频率（PRF）和壁运动滤波器对从健康参与者颈总动脉获取的时空图像相关（STIC）数据集中获得的三维（3D）功率多普勒血管化血流指数（VFI）和容积搏动指数（PI）的影响。
我们获取了11个STIC数据集，每个PRF值（范围从0.6至9.0 kHz）对应一个数据集。从这些STIC数据集中包含的440个静态3D数据集中确定血管化血流指数和容积PI值。此外，针对PRF值为0.6、3.3和10 kHz的不同壁运动滤波器值进行离线处理，获取了3组射频数据。
我们构建了VFI曲线并观察到两种模式：低PRF时的平坦模式和高PRF时的三相模式，这与该血管已知的脉冲波多普勒轮廓相关。低PRF设置下容积PI值约为0，并随PRF增加而升高。对射频数据的分析表明，增加壁运动滤波器值会逐渐滤除低速功率多普勒信号，同时保留高速信号，从而能够区分整个心动周期中的综合功率多普勒信号速度。
我们得出结论，PRF和壁运动滤波器对3D功率多普勒指数和容积PI有显著影响，并且在频谱多普勒波的舒张期测量到最小VFI值时使用PRF值可能会验证容积PI的使用。
